Family fairness?

My boyfriends family have just moved house and we went over for the weekend to help out and also to move his cats there as they aren't happy where we're living atm.
This weekend though he was meant to be coming away with me for a family weekend away for my uncles birthday and he's bailed to go back to his family's house because of the cats, its really annoyed me but I was wondering what your opinions where and what you would do? As I'm just pretending it hasn't bothered me